The Formation of Spore-Like Akinetes: A Survival Strategy of Filamentous Cyanobacteria

Some cyanobacteria of the order Nostocales can form akinetes, spore-like dormant cells resistant to various unfavorable environmental fluctuations. Akinetes are larger than vegetative cells and contain large quantities of reserve products, mainly glycogen and the nitrogen storage polypeptide polymer cyanophycin. Akinetes are enveloped in a thick protective coat containing a multilayered structure and are able to germinate into new vegetative cells under suitable growth conditions. Here, we summarize the significant morphological and physiological changes that occur during akinete differentiation and germination and present our investigation of the physiological function of the storage polymer cyanophycin in these cellular processes. We show that the cyanophycin production is not required for formation and germination of the akinetes in the filamentous cyanobacterium Anabaena variabilis ATCC 29413.

Automated summary

Some cyanobacteria of the order Nostocales can form spore-like akinetes for survival in unfavorable environmental conditions. These akinetes are larger in size, contain abundant reserve products, and can germinate into new vegetative cells. The production of the storage polymer cyanophycin is not essential for the formation and germination of akinetes in a filamentous cyanobacterium Anabaena variabilis ATCC 29413.